diff --git a/src/main/scala/uncore/tilelink2/Fragmenter.scala b/src/main/scala/uncore/tilelink2/Fragmenter.scala
index f9472f48..cec91c59 100644
--- a/src/main/scala/uncore/tilelink2/Fragmenter.scala
+++ b/src/main/scala/uncore/tilelink2/Fragmenter.scala
@@ -26,7 +26,7 @@ class TLFragmenter(minSize: Int, maxSize: Int, alwaysMin: Boolean = false) exten
   }
   def shrinkTransfer(x: TransferSizes) =
     if (!alwaysMin) x else
-    if (x.min <= minSize) TransferSizes(x.min, minSize) else
+    if (x.min <= minSize) TransferSizes(x.min, min(minSize, x.max)) else
     TransferSizes.none
   def mapManager(m: TLManagerParameters) = m.copy(
     supportsAcquire    = TransferSizes.none, // this adapter breaks acquires
diff --git a/src/main/scala/uncore/tilelink2/Parameters.scala b/src/main/scala/uncore/tilelink2/Parameters.scala
index 9a909261..0fb438ab 100644
--- a/src/main/scala/uncore/tilelink2/Parameters.scala
+++ b/src/main/scala/uncore/tilelink2/Parameters.scala
@@ -50,6 +50,7 @@ case class TransferSizes(min: Int, max: Int)
   require (min >= 0 && max >= 0)
   require (max == 0 || isPow2(max))
   require (min == 0 || isPow2(min))
+  require (max == 0 || min != 0) // 0 is forbidden unless (0,0)
 
   def none = min == 0
   def contains(x: Int) = isPow2(x) && min <= x && x <= max